After two years fighting their 'David and Goliath' battle against seismic tests to search for oil and gas deposits offshore of their community, hundreds of protesters in Ottawa and Nunavut, along with celebrities and activists around the world, showed their support.

"I wasn't expecting this," said Jerry Natanine, amidst a crowd of 300 demonstrators. "We thought no one would care."

The former mayor of Clyde River has been leading the charge on his community's legal challenge of the National Energy Board's decision to allow seismic testing — and it hasn't been easy.

"The last two years we've been through hell," he said.

"We don't want anyone else to face that, because as a community we've had real hard times, stressing about whether our food source is going to be all gone."

If the majority of Canada's nine Supreme Court justices side with the Nunavut community, Natanine could get his wish.

This case could set a precedent that redefines the Crown's duty to consult with Indigenous groups before development projects get the go-ahead.

Jerry Natanine, Clyde River's former mayor, stands outside the Supreme Court of Canada in Ottawa. A rally in support of the hamlet of Clyde River can be seen behind him. (Waubgeshig Rice/CBC)

'The soul of Canada'

A protest took place in Ottawa Tuesday, as dozens of supporters stood in solidarity with the Nunavut hamlet of Clyde River as it prepares to present its argument against seismic testing to the Supreme Court. (Waubgeshig Rice/CBC)

Because the potential consequences are so serious, Clyde River says the level of consultation provided was not sufficient.

"This case is really about the soul of Canada," he said.

"Are we going to be a nation that takes Indigenous and Inuit rights seriously? Or are we going to allow Indigenous rights to be reduced to a due diligence checklist for industry proponents to check off?"

The facts of the case have already been set. At issue is what it takes for Canada to fulfil its constitutional duty to consult Indigenous communities.

During today's hearing, Hasan argued the meetings held by the seismic testing companies in four Nunavut communities just weren't enough.

"When they were going up there telling us what they were going to do, it wasn't a consultation," Natanine said. "They just told us what they were going to do and didn't answer our questions."

Threat to marine animals, argues hamlet

The companies would use airguns to produce pulses of sound waves under the waters offshore from a number of Baffin Island communities.

According to a project overview on the National Energy Board website, the sound created by the airguns "is estimated to be 230 decibels at a distance of one metre away, and will be repeated every 13 to 15 seconds, 24 hours a day while operating."

Protesters from across Canada are in Ottawa today to support Clyde River, Nunavut, in its legal fight against seismic testing. (submitted by Manasie Cousins)

Inuit in Clyde River are concerned the sounds may be loud enough to scare away or deafen the marine mammals they rely on for food — a significant worry for a region where food insecurity is "a very serious problem."

In Nunavut, basic food items in grocery stores can cost up to three times higher than in the rest of Canada.

The latest government statistics pegged the average cost in Nunavut of a one-kilogram bag of apples at $7.26 and a 2.5-kilogram bag of flour at $13.70.

Clyde River mayor James Qillaq thanks the crowd for coming and "supporting our community and our way of life" pic.twitter.com/z5zVyf8mKs

Supreme Court will issue 'the final word' ​

In the morning, the Supreme Court heard from another Indigenous community: the Chippewas of the Thames.

Inuit from communities across Canada are gathering outside the Supreme Court of Canada to support a court case which could define the government's constitutional duty to consult. (submitted by Manasie Cousins)

The First Nation argued the National Energy Board approved a development project without proper consultation — this time a partial reversal of a pipeline carrying heavy crude.

"Both cases at their core are about the duty to consult and the crown's obligation to respect Indigenous rights, Inuit rights," said Hasan.

"Quite literally, these cases will affect every single development project across the country."

Meanwhile, lawyers for Enbridge Pipelines Inc. argued the National Energy Board used "more than reasonable" efforts to hear about the potential impacts on the rights and interests of Indigenous communities.

The company also cautioned the court not to impose "unnecessary and impractical" regulations, which would make it challenging for regulators to do their work.

The Supreme Court of Canada will now consider today's arguments. It will likely be several months until a decision is reached.